Book Description

The International Linear Collider (ILC), a next generation particle accelerator, will smash electron and positron bunches at up to 500 GeV (1000 GeV after a planned upgrade). The 31-km long collider's experiments will help scientists to understand the fundamental constituents of matter. Located at the ILC detector's forward region, the BeamCal is a highly segmented (> 90,000 channels) calorimeter that will serve three main purposes: ensure hermeticity of the detector for low polar angles, reduce the backscattering from pairs into the detector center, and provide a low-latency signal for beam diagnostics. The BeamCal specifications in terms of radiation tolerance, noise suppression, signal charge, pulse rate and occupancy pose unique challenges for the front-end and readout electronics design. Designed for the 180-nm TSMC mixed-signal technology, The Bean -- BeamCal Instrumentation IC -- is a 32-channel front-end and readout ASIC that will address the BeamCal instrumentation requirements. By employing a charge-sensitive amplifier and a switched-capacitor reset circuit, the Bean will process the input charge signals at the ILC pulse rate. Each channel will have a 10-bit successive approximation register analog-to-digital converter and digital memory for readout purposes. The Bean will also feature a fast feedback adder, capable of providing an 8-bit, low-latency output for beam diagnostics purposes. This work presents the design and characterization of The Bean prototype, a 3-channel ASIC that proves the principle of operation described.